The present invention relates to the directional lighting of objects having thee-dimensional surfaces, such as plants, sculptures and other defined objects.
It particularly relates to the glare-free illumination of objects intended to be centripetally viewed by a plurality of observers grouped around such lighted object. Conventional methods used to light three-dimensional objects involve the use of spotlights, ceiling lights, track lights and the like, normally beamed at and around the object to be illuminated from a distance, normally of several meters. Such lighting methods and devices have a number of disadvantages. A primary disadvantage stems from the distance at which conventional lights are mounted from the object to be illuminated. This causes not only loss of lumens, but a scattering of light beyond the confines of the object. It is obvious that, the greater the distance, the more difficult it is to economically direct light with precision at three-dimensional objects, especially objects having irregular configurations. An illustration would be a tall or spindly plant or an irregularly shaped object, in the lighting of which much of the light passes by and through such an object.
A serious drawback of such lighting methods lies in the glare produced by ceiling lights and spotlights, which results in discomfort to the eyes of observers.
Glare-free lighting devices positioned in close proximity to the objects to be illuminated are known and employed in the conventional lighting of two-dimensional surfaces such as paintings, murals, wall hangings and the like. Such devices, mounted for instance at the top or bottom edge of a painting, are however, not suitable for lighting objects having three-dimensional surfaces, such as standing or hanging indoor plants, or outdoor plants, in a decorative, pleasing and effective manner. The present invention is specifically directed towards the illumination of objects having three-dimensional surfaces and does not relate to the lighting of two-dimensional, planar, or essentially flat areas, such as floors and walls, or other flat objects such as paintings and tapestries.
Lighting devices, such as spotlights, for lighting indoor and outdoor plants are used extensively in the illumination of specific three-dimensional objects. The light from such light sources, illuminating for instance the foliage of plants, normally emanates from one source or from several discrete light sources placed at a distance from the object. The disadvantages of these devices are several. First, the light originating at a single source or even at several sources, positioned at a distance and directed at a plant, illuminates only that facet of the foliage which faces such light sources, i.e. one side of the plant. Also, such light usually shines across and through the plant, which is inefficient; more importantly, the naked light shines directly into the eyes of persons facing the light source. If the illuminated plant is thick or dense enough to prevent light from shining through it in such annoying fashion, it follows that the side of the plant facing away from the light source receives no illumination at all. If, in order to overcome these drawbacks, several light sources are disposed around the object to be illuminated, the equipment cost and operating expenses are correspondingly multiplied. Furthermore, the lighting effect of such devices is not uniform and juxtapositioned persons will be exposed to glare.
The present invention therefore is intended to be useful in lighting three-dimensional objects involving multidirectional and centripetal (radially inward) viewing by juxtapositioned observers on opposite sides of the object to be illuminated, irrespective of whether the lighted object is transparent, has openings, or is irregularly shaped. Using currently available devices, the pleasing effect of lighting the foilage of plants and shrubs is destroyed when the human eye is directly exposed to the light source.
The type of outdoor lighting device commonly used, which has reflectors directing light downwardly in a glare-free manner towards the ground is capable of illuminating only flowers or short plants; whereas the present invention does not depend on the height, shape or level of the object to be illuminated.
As previously stated, whenever spotlights or similar lights are used in illuminating plants, juxtapositioned observers, i.e. observers positioned on the side of the plant opposite to that where such light source is mounted, are exposed to the unpleasant glare of directly viewed light. For these reasons, known lighting devices are unsatisfactory when objects are displayed for viewing from all sides, e.g. free standing museum exhibits. The present invention addresses problems of this nature, as for instance lighting a sculpture in such fashion that observers grouped in a circle around the exhibit will each have an unobstructed, glare-free view of the uniformly lighted sculpture, or even of a sculpture having selected individual features lighted differently from the rest.
It therefore is a principal object of the invention to directionally illuminate three-dimensional objects, such as plants and sculptures positioned above, at, or below the eye level of observers in such a manner that the source of light is not directly visible and glare is avoided.
It is another object to minimize the loss and consumption of lumens by placing the light source in close proximity to the object to be illuminated so as to shorten to the absolute practical minimum the indirect path the light has to travel in illuminating the object.
It is still another object of the invention to avoid the scattering of light inherent in other indirect lighting methods.
It is yet another object to provide an illuminating system and luminaire which are economical and simple to manufacture, install and maintain, and which are highly efficient in operation.
It is another object of the present invention to provide means for supplying to tropical and other plants heated, moist vapor in a sustained manner while illuminating the plant.
It is still another object to indirectly light three-dimensional objects in a novel, decorative and pleasing manner.
Definitions
As stated, the avoidance of glare is a primary object and result of the methods, systems and devices described herein. The Encyclopaedia Britannica published in 1956 defines glare as follows:
"When brightness becomes irritating it is recognized as "glare." Glare contributes more to the poor quality of a lighting system than any other factor. Glare may depend upon several conditions present in the lighting system: (1) high brightness of the source; (2) high brightness contrast between the source and the background; (3) location of the source in the field of view; (4) the total volume of the light entering the eye; and (5) the time of exposure to the brightness source. The correction of any one of these contributing factors becomes simple when it is considered individually. Because of the injurious effect of glare, either direct as from a source, or reflected from some object which reflects a specular image, bare lamps exposed in any plane should never be used. It is of prime importance that all forms of glare be controlled properly."
The term "source of light" as used herein is intended to include where appropriate a combination of more than one lamp positioned at a lighting hub or arranged in such manner as to function as a central light source emitting light in essentially centrifugal directions. The term "light mantle" as used herein denotes a wall or band of light of predetermined width and configuration. The term "object" in the phrase "object to be illuminated" is intended to include, where appropriate, the holder or support for sculptures, or associated elements of such objects as for instance the flower pot of a plant. The term "reflective" as used hereinafter is defined as "light-reflective". The term "bowl-shaped" or "dished" is intended to refer to concave structures, such as vessels having an approximately parabolic, elipsoid or hemispheric configuration at their bottom, irrespective of the configuration of the rest of the wall surface between the bottom and the rim of the vessel.
The various objects and advantages of the invention will become apparent from the following description and accompanying drawings. While the description and drawings are for illustrative purposes primarily directed to plants, it should be obvious that the methods, devices and systems claimed are equally suitable for and applicable in the illumination of other objects, such as sculptures, antiques, statues, art objects, mineral exhibits, theatrical devices, stage props, museum and show pieces of any nature.